1. Field of the Invention
The present invention relates to a lens module and a method for manufacturing thereof.
2. Description of the Related Art
In recent years, a compact and thin type imaging unit has been installed in a portable terminal such as a mobile telephone or a personal digital assistant (PDA). In general, such an imaging unit includes a solid-state imaging device, such as a charge coupled device (CCD) image sensor or a complementary metal-oxide semiconductor (CMOS) image sensor, and a lens to form a subject image on the solid-state imaging device.
To reduce the cost of an imaging unit, there is a demand for streamlining a method for manufacturing a lens so as to enable the lens, which is to be mounted on the imaging unit, to be manufactured at low cost and in large amounts. Such a lens is produced in accordance with the following procedure. First, a lens array having a configuration in which a plurality of lens portions are integrally formed on a substrate portion is manufactured, and then the plurality of lens portions are respectively separated by cutting the substrate portion. Subsequently, the lens is mounted on the imaging unit.
A method for manufacturing a lens module has been disclosed in JP2009-251249A. In the method, the lens module is manufactured by bonding a wafer level lens array, in which a substrate portion and a plurality of lens portions are integrally formed, to another wafer level lens array using an adhesive.
The substrate portion is cut into the lens module of which the lenses are bonded to each other, and then the lens module is mounted on an imaging unit. The imaging unit is mounted on a circuit substrate, such as a portable terminal, by a reflow mounting method.